Ha! - yes, the dashpots. You need the correct grade of oil and keep them at the correct level.
These are great cars buddy. In fact, just up the road from me is a company that has specialised in rebuilding / renovating these for as long as I can remember - and they are still there.

I used to mess with the Mk111 Spitfires as a hobby - they are great fun as well.
Parts are cheap and easy to get over here.